Answer to Question 1
ANS: A
Opening snap is caused by the opening of a stenotic mitral or tricuspid valve and is heard early in diastole along the lower left sternal border. It is high pitched and heard best with the diaphragm of the stethoscope. Friction rubs occur frequently after a myocardial infarction (MI) or with pericarditis. The sound is a high-pitched grating, scratching soundresulting from inflammation of the pericardial sacthat issues from the parietal and visceral surfaces of the inflamed pericardium as they rub together.
Answer to Question 2
ANS: C
S4, also called an atrial gallop, occasionally occurs in a normal adult or well-trained athlete but is usually due to increased resistance to filling of the ventricle. Possible causes of a left-sided S4 include HTN, CVD, cardiomyopathy, and aortic stenosis. Possible causes of a right-sided S4 include pulmonic stenosis and pulmonary HTN. S4 is heard just before S1 with the patient supine or in the left lateral recumbent position. The sound can be as loud as S1 and S2. S4 is not heard in patients with chronic atrial fibrillation due to no distinct atrial kick.
